Where is it cool in September?

An escape from the heat, without needing a coat. Ranked from 296 travel destinations using ERA5 climate averages — what September is normally like, not what the weather will do next week.

See it on the map

Top 20 by September weather

Day and night temperatures are monthly averages of daily highs and lows. Rain is an average across the whole month. Places with the same rating have equally good weather for this; among them, the one covered by more language editions of Wikivoyage, the open travel guide, is listed first. The bar under each place shows its other good months — click one to jump there.
#	Place	Day	Night	Rain	Rating
1	London, United Kingdom	19°C	12°C	1.8 mm/day	Excellent
2	Berlin, Germany	21°C	12°C	1.4 mm/day	Excellent
3	Prague, Czechia	20°C	11°C	2.6 mm/day	Excellent
4	Sydney, Australia	19°C	13°C	1.9 mm/day	Excellent
5	Warsaw, Poland	20°C	12°C	1.6 mm/day	Excellent
6	Amsterdam, Netherlands	19°C	14°C	2.3 mm/day	Excellent
7	Stockholm, Sweden	17°C	11°C	1.4 mm/day	Excellent
8	Buenos Aires, Argentina	18°C	11°C	1.7 mm/day	Excellent
9	Hamburg, Germany	20°C	12°C	1.6 mm/day	Excellent
10	Sarajevo, Bosnia and Herzegovina	19°C	10°C	2.6 mm/day	Excellent
11	Kraków, Poland	20°C	11°C	2.8 mm/day	Excellent
12	Copenhagen, Denmark	18°C	12°C	1.7 mm/day	Excellent
13	Riga, Latvia	18°C	12°C	1.6 mm/day	Excellent
14	Perth, Australia	19°C	11°C	1.0 mm/day	Excellent
15	Santiago, Chile	17°C	5°C	1.2 mm/day	Excellent
16	Tallinn, Estonia	16°C	11°C	2.0 mm/day	Excellent
17	Cape Town, South Africa	16°C	12°C	1.4 mm/day	Excellent
18	Bogotá, Colombia	18°C	9°C	1.4 mm/day	Excellent
19	Vilnius, Lithuania	18°C	11°C	1.2 mm/day	Excellent
20	Lima, Peru	20°C	14°C	0.3 mm/day	Excellent

What this ranking does and does not tell you

It rates the weather only — daytime and night temperature, rain and sunshine. It says nothing about what there is to see or do, prices, crowds or safety; that part of the decision is yours.

The candidates are 503 established travel destinations, not every town on Earth, so a place missing here may simply not be on the list.

Looking for something else in September?

warm hot dry sunny mild

The same question, another month

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